U.S. patent number 7,458,494 [Application Number 11/357,814] was granted by the patent office on 2008-12-02 for surgical stapler with sound producing mechanism to signal the completion of the stapling process.
This patent grant is currently assigned to MANI, Inc.. Invention is credited to Masatoshi Fukuda, Takashi Ina, Toshiharu Kamei, Kanji Matsutani.
United States Patent |
7,458,494 |
Matsutani , et al. |
December 2, 2008 |
Surgical stapler with sound producing mechanism to signal the
completion of the stapling process
Abstract
A surgical stapler has a body capable of containing a plurality
of staples in an aligned state; a ram provided inside the body,
having a central concave portion and pressure armatures on both
sides of the concave portion; an anvil that, when the armatures of
the ram contact both sides of a crown of a staple, forces the
center of the crown into the concave portion of the ram; and a
trigger rotatably supported on the body so as to cause relative
movement between the ram and the anvil. The trigger as a moving
member and the body as another member strike each other so as to
produce a sound and/or a vibration indicating that a staple
sandwiched between the ram and the anvil is bent by the advance of
the anvil into the concave portion of the ram and bending of the
staple is completed.
Inventors: |
Matsutani; Kanji (Utsunomiya,
JP), Fukuda; Masatoshi (Utsunomiya, JP),
Kamei; Toshiharu (Utsunomiya, JP), Ina; Takashi
(Utsunomiya, JP) |
Assignee: |
MANI, Inc. (Tochigi,
JP)
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Family
ID: |
36589287 |
Appl.
No.: |
11/357,814 |
Filed: |
February 21, 2006 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060191974 A1 |
Aug 31, 2006 |
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Foreign Application Priority Data
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Feb 28, 2005 [JP] |
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2005-052330 |
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Current U.S.
Class: |
227/175.1;
227/19 |
Current CPC
Class: |
A61B
17/0684 (20130101); A61B 34/76 (20160201); A61B
2090/0811 (20160201) |
Current International
Class: |
A61B
17/068 (20060101) |
Field of
Search: |
;227/181.1,175.1,19,120,176.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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H05-003879 |
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Jan 1993 |
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JP |
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2000-217829 |
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Aug 2000 |
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JP |
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Primary Examiner: Gerrity; Stephen F
Attorney, Agent or Firm: Farrar; Joseph P.
Claims
What is claimed is:
1. A surgical stapler comprising: a body capable of containing a
plurality of staples in an aligned state; a ram provided inside
said body, having a central concave portion and pressure armatures
on both sides of the concave portion; an anvil that, when the
armatures of said ram contact both sides of a crown of a staple,
forces the center of the crown into the concave portion of the ram;
and a trigger rotatably supported on the body so as to cause
relative movement between the ram and the anvil, wherein the
staples are circular in cross-section, a front edge of a bottom
surface of the concave portion of the ram has a slanted surface
slanting outwardly in a direction away from the central concave
portion of the ram, a ridge line of a front edge of said slanted
surface contacting a staple on the anvil at a position offset to
the rear of a center line of the staple.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a surgical stapler for suturing
tissue, and more particularly, to a surgical stapler that enables
the user to sense clearly the suturing operation, that is, the
completion of the bending of the staple.
2. Background of the Invention
In surgical operations, metal staples are bent to suture shut an
incision. As that which is used for this purpose, the surgical
staplers described in Japanese Laid-Open Patent Application
Publication No. Heisei 05-3879 and Japanese Laid-Open Patent
Application Publication No. 2000-217829 are conventionally
known.
FIG. 3 shows the process of bending a staple using these
conventionally known surgical staplers.
A staple 1 penetrates the tissue and remains imbedded in the tissue
until the incision heals. Accordingly, it is important that the
staples be both sufficiently strong and do not adversely affect the
tissue, and for these reasons austenitic stainless steel, which
does not rust, is used for the staple 1. The staple 1 consists of
rounded wire with a diameter of approximately 0.5 mm that is cut
and then bent in the shape of a "C". The straight portion of the
staple 1 is called the crown 1a and the portions bent from both
ends of the crown 1a are called the legs 1b. In order to pierce
tissue easily the tips of the legs 1b are pointed.
FIG. 3A shows an initial state, with a ram 3 moving toward an anvil
4 and the staple 1 held between the anvil 4 and the tips of
pressure armatures 3a formed on both sides of a concave part 3b of
the ram 3.
FIG. 3B shows an intermediate state, in which the ram 3 further
descends, the anvil 4 reaches the entrance to the concave part 3b,
and the staple 1 is partially bent by the armatures 3a.
FIG. 3C shows a final state, in which the ram 3 continues to
descend, the anvil 4 enters the concave part 3b and presses against
the crown 1a of the staple 1 at the concave part bottom surface
3b', and the staple 1 is bent at right angles at both ends of the
anvil 4 in the direction of the breadth of the anvil 4, closing the
staple 1. This state is the state in which the bending of the
staple 1 is completed. In this state, the crown 1a indicates the
top part of the staple, which is now a rectangular shape.
In the process of moving from the state shown in FIG. 3B to the one
shown in FIG. 3C, the tips of the staple 1 enters the tissue,
completing one suture. If the incision is a large one, suturing is
repeated as many times as needed. It should be noted that, in this
specification, the staple in its closed state indicates a state in
which, when the staple is bent between the ram and the anvil, the
most fully bent portion is completely bent, and includes not only a
state in which the tips of the legs 1b of the staple 1 are
completely in contact but also are just slightly separated from
each other.
The surgical stapler described in Japanese Laid-Open Patent
Application Publication No. Heisei 05-3879 arranges a plurality of
C-shaped staples in an aligned state astride the top of the anvil
plate inside the body of the stapler and pushes the staples forward
with a torsion spring. The forward edge of the anvil plate is the
anvil, with the ram disposed substantially perpendicular to the
anvil. The anvil is fixed, and the ram is advanced toward and
withdrawn from the anvil by a rotary trigger, bending the staple
fed to the front of the anvil into its final rectangular shape.
The surgical stapler described in Japanese Laid-Open Patent
Application Publication No. 2000-217829 has a magazine containing a
plurality of staples in a state of alignment, and a ram and an
anvil that are moved in tandem by a trigger. Operating the trigger
causes the ram and the anvil to pick out a single staple, hold it,
and move together to bend the staple into its final form.
FIG. 4 is a diagram showing an external view of a surgical stapler
10 described in Japanese Laid-Open Patent Application Publication
No. Heisei 05-3879. The same ram and anvil as shown in FIGS. 3A, 3B
and 3C are contained in the stapler body 11, together with a
plurality of staples 1. As the trigger 12 approaches the body 11,
the forward edges of the ram and the anvil approach each other
within the body 11, bending the staple held at the front of the
anvil into its final form.
FIG. 5 is a diagram showing the structure of a surgical stapler 20
described in Japanese Laid-Open Patent Application Publication No.
2000-217829. The surgical stapler 20 comprises a magazine 22
containing a plurality of staples 1 in a state of alignment, a ram
23, an anvil 24 and a trigger 25 inside the staple body 26.
The trigger 25 revolves around a revolving shaft 27 provided on the
body 26. A hole that engages the revolving shaft 27 is a slot 28. A
pin 29 and a V-shaped groove 30 guide the trigger 25 as it
revolves. Such a structure enables the trigger 25 to move and
revolve with respect to the body 26 of the stapler, such that when
force is applied to the trigger 25, the trigger can rotate as its
axis of rotation moves toward the ram 23. As a result, the distance
from the axis of rotation of the trigger 25 to the grip widens,
enabling a large torque to be generated with a relatively small
force.
However, the surgical staplers described in Japanese Laid-Open
Patent Application Publication Nos. 5-3879 and 2000-217829 suffer
from the drawback that the user gets no particular sensation
indicating that the staple has been bent into its final form when
that action is completed as shown in FIG. 3C. At most, just prior
to completion of the bending of the staple into its final form, the
movement of the trigger 25 becomes easier than it has been up to
that point, and then becomes harder, which is the only indication
that the suture is completed. However, after the movement of the
trigger 25 gets easier it is not easy to tell how hard the movement
will become, and it is easy to think that the suture is completed
when in fact it is not.
SUMMARY OF THE INVENTION
Accordingly, the present invention is conceived as a solution to
the above-described problems of the conventional art, and has as
its object to provide a surgical stapler that enables the user to
sense clearly the suturing operation, that is, the completion of
the bending of the staple.
To achieve the above-described object, the present invention
provides a surgical stapler comprising:
a body capable of containing a plurality of staples in an aligned
state;
a ram provided inside said body, having a central concave portion
and pressure armatures on both sides of the concave portion;
an anvil that, when the armatures of said ram contact both sides of
a crown of a staple, forces the center of the crown into the
concave portion of the ram; and
a trigger rotatably supported on the body so as to cause relative
movement between the ram and the anvil,
a moving member striking another member so as to produce a sound or
a sensation of impact after a staple sandwiched between the ram and
the anvil is bent by the advance of the anvil into the concave
portion of the ram and bending of the staple is completed.
In addition, preferably, after bending of the staple is completed,
a load on the staple from the ram increases while the positions of
the ram and the anvil do not change, and the positions of the ram
and the anvil can no longer be maintained and thus shift to new
positions when the load reaches a certain level, such change
causing a moving member to strike another member.
The moving members may include, for example, the trigger, ram or
anvil. The other member, which is a strikable member, is located on
the trajectory of the moving member such as the trigger, ram or
anvil, and consists of the stapler body if the moving member is the
trigger and consists of the anvil if the moving member is the
ram.
In addition, preferably, the staples are circular in cross-section,
a front edge of a bottom surface of the concave portion of the ram
has a slanted surface, a ridge line of a front edge of said slanted
surface contacting a staple on the anvil at a position offset to
the rear of a center line of the staple, the ridge line of the
front edge of the slanted surface of the ram further pressing the
crown of the staple when the surgical stapler is closed, such that
the ram slides across a front surface of the staple and strikes the
anvil so as to produce a sound or a sensation of impact.
The above-described structure works as follows:
When the staple is bent, at first, such deformation (bending) of
the staple proceeds substantially proportionally to the load
exerted on the staple. However, as deformation proceeds, the load
reaches its maximum and thereafter begins to decline, but
deformation of the staple continues. At this point, the trigger
begins to move very easily and then gets harder to pull, and when
force is applied against this resistance of the trigger the
surgical stapler is closed. If at this point the surgical stapler
is constructed so that the trigger and the body contact each other,
then when bending of the staple into its final form is completed
the trigger strikes the body and produces a vibration or a sound of
impact.
As a construction in which the ram and the anvil strike each other,
there is one in which a front edge of the bottom surface of the
concave portion of the ram is a slanted surface. Just before the
bending of the staple is completed, the ridge line of the ram front
edge side of the slanted surface contacts the round staple on the
anvil at a point just below and behind the top of the staple. The
force applied to the trigger is transmitted directly to the staple,
pressing the staple against the anvil, but as the force on the
trigger increases, the ram quickly slips over the surface of the
staple, the slanted surface contacts the staple, the staple is
pushed out of the surgical stapler along the slanted surface and
the ram strikes the anvil with force, producing a sound or
vibration of impact. Moreover, the staple is securely expelled to
the outside of the surgical stapler by the slanted surface.
It should be noted that, alternatively, the surgical stapler may be
constructed so that the ram and the anvil do not strike each other
but instead remain a slight distance apart, while the trigger
strikes another member such as the body of the surgical
stapler.
According to the present invention, when the bending of the staple
into its final form is completed, one member strikes another member
so as to produce a vibration or a sound, thereby enabling the user
of the surgical stapler to sense clearly that suturing is completed
so as to prevent stopping of the stapling before the staple is
fully bent in place and the suture is completed.
Other features, objects and advantages of the present invention
will be apparent from the following description when taken in
conjunction with the accompanying drawings, in which like reference
characters designate the same or similar parts throughout the
figures thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B are diagrams showing the surgical stapler shown in
the conventional example shown in FIG. 4 improved to achieve the
object of the present invention, with FIG. 1A showing the surgical
stapler prior to bending of the staple and FIG. 1B showing the
surgical stapler in a state in which the bending of the staple is
completed;
FIGS. 2A and 2B are diagrams showing a second embodiment of the
present invention;
FIGS. 3A, 3B and 3C are diagrams showing the process of the
surgical stapler bending the staple, showing the start, middle and
end states of the stapling process, respectively;
FIG. 4 is a diagram showing an external view of a conventional
surgical stapler; and
FIG. 5 is a diagram showing the structure of another conventional
surgical stapler.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will now be
described in detail, with reference to the accompanying
drawings.
FIGS. 1A and 1B are diagrams showing the surgical stapler shown in
the conventional example shown in FIG. 4 improved to achieve the
object of the present invention, with FIG. 1A showing the surgical
stapler prior to bending of the staple and FIG. 1B showing the
surgical stapler in a state in which the bending of the staple is
completed.
With a surgical stapler 10 shown in FIGS. 1A, 1B, one end of a
trigger 12 is supported within a body 11 of the surgical stapler 10
so as to rotate freely. A plate cam 12b is formed on the trigger
12, and when the trigger 12 revolves clockwise around a shaft 12a,
the plate cam 12b presses a projection 3c on a ram 3 and the ram 3
moves downward in the diagram. When the force applied to the
trigger 12 is released, the ram 3 returns upward impelled by the
force of a spring, not shown, and the trigger 12 revolves
counterclockwise to return to its original position. A plurality of
staples 1 are held so as to straddle an anvil 4, although in FIG.
1A only the first staple 1 is shown. This staple 1 is pushed in a
direction perpendicular to the surface of the paper on which the
diagram is drawn by a spring, not shown, and prevented from flying
outward by a cover, not shown, that covers the body 11.
When a front edge of the trigger 12 is pressed and the trigger 12
rotated in the clockwise direction, the plate cam 12b presses the
ram 3 downward, bending and closing the staple 1 into its final
form as in the process shown in FIGS. 3A, 3B and 3C. Then, just
before reaching the state shown in FIG. 3C, the load on the trigger
12 rapidly decreases and the rotation of the trigger quickens,
completing the bending of the staple 1. In this embodiment of the
present invention, when this bending is completed, the trigger 12
strikes the body 11 so as to produce a sound of impact. With such a
construction, the user can sense clearly that the suture is
complete, thus preventing incomplete suturing of an incision.
FIGS. 2A and 2B are diagrams showing a second embodiment of the
present invention. In this embodiment, a slanted surface 3d is
formed on a bottom surface 3b' of a concave portion of the ram 3,
forming a ridge line 3e at the boundary between the bottom surface
3b' of the concave portion and the slanted surface 3d. The trigger
may be any suitable form, including the trigger 12 shown in FIG. 4
or the trigger 25 shown in FIG. 5. The trigger 12 shown in FIG. 4
is used in the following description.
When force is applied to the trigger 12, the trigger 12 begins to
revolve in the clockwise direction, the plate cam 12b of the
trigger 12 presses on the projection 3c of the ram 3 and begins to
push the ram 3. Soon, as shown in FIG. 3A, the tips of pressure
armatures 3a contact the crown of the staple 1. Then, as the force
applies to the trigger 12 continues to increase, the staple 1
begins to bend as shown in FIG. 3B. At this point, the force
exerted on the trigger 12 and the degree of bending of the staple 1
increase substantially proportionally. When the force applied to
the staple 1 increases to a certain level the staple 1 reaches its
yielding point, after which the force applied to the trigger
decreases and the staple continues to bend. At the stage at which
the bending of the staple 1 is substantially completed as shown in
FIG. 3C, the bottom surface 3b' strikes the crown of the staple 1
along the ridge line 3e. Thereafter, as further force is applied to
the trigger 12, the force F exerted on the ram 3 increases. At the
same time, a plurality of staples are contained within the surgical
stapler and impelled to the left in FIG. 2A by a force f of a
spring, not shown. A top surface of the anvil 4 is not level but
inclined at an angle .theta., with the forward edge thereof slanted
upward.
While the force F is small, the staple 1 is pressed against the
anvil 4 and the relative positions of the ram 3 and the anvil 4 do
not change. However, once the force F exceeds a certain limit, the
sum of the angular moment of the force F and the force f overcome
the frictional force of the anvil 4 and the staple 1. At that
moment, the ridge line 3e slips from point B off the outer
peripheral surface of the staple 1 and the slanted surface 3d
pushes the staple 1 to the left in the diagram, releasing the
staple 1 from the anvil 4. At the same time, the ridge line 3e or
the bottom surface 3b' of the ram 3 sharply strikes the anvil 4,
producing for example a sharp metallic click or the like that is
the sound of impact, by which the user of the surgical stapler can
confirm that the suture is completed. Alternatively, a vibration
may be produced instead of the sound of impact to achieve the same
purpose.
It should be noted that, although in the above-described
embodiments the ram 3 and the anvil 4 strike each other as to
produce a sound or a vibration, alternatively, the surgical stapler
may be constructed so that the ram 3 and the anvil 4 do not strike
each other but instead remain a slight distance apart while the
trigger 12 strikes the body 11 of the surgical stapler.
As many apparently widely different embodiments of the present
invention can be made without departing from the spirit and scope
thereof, it is to be understood that the invention is not limited
to the specific preferred embodiments described above thereof
except as defined in the claims.
* * * * *